Electrical switch



Nov. 4 1924.

W. F. FULTON ELECTRICAL SWITCH Filed Aug. 16, 1922 P "AMT nm 5 i W'. F. Eu Lion,

WITNESSES A TTORNEYS WILLIAM FARRELL FULTON,

1,513,901 PATENT OFFICE.

OF SHREVEPORT, LOUISIANA.

ELECTRICAL SWITCH.

Application filed August 16, 1922. Serial No. 582,224.

7'0 all whom it may concern:

Be it known that I, WILLIAM F. FULTON, a citizen of the United States, and a resident of Shreveport, in the parish of Caddo and State of Louisiana, have invented certain new and useful Improvements in Electrical Switches, of which the following is a specifi cation.

This invention relates to improvements in electrical switches.

The present invention more particularly relates to improvements in what is commonly referred to as push button switches and usually employed in connection with electric lighting systems in dwellings or the like.

The invention has for its object to provide a switch of this character which is adapted to be operated for instantaneously making or closing an electrical circuit and which is adapted to delay the opening of the electrical circuit a predetermined interval after the same has been operated for opening said circuit.

It is also within the scope of the objects of the invention that the switch be exceedingly simple in construction and not subject to etting out of working order.

Uther objects will hereinafter appear.

The invention is illustrated by way of example in the accompanying drawing, in which- Figure 1 is a vertical sectional view of the switch when mounted in a wall or the like.

Figure 2 is a top lan view of the same when the cover there or is removed.

Figure 3 is a vertical sectional view of the cylinder and associated piston employed in the switch.

Figure 4 is a top plan view of the other end of the piston shown, in Figure 3, and Figure 5 is a detail view of the electrical circuit closing means.

Referring to the drawings more particularly, W indicates generally a wall in which there may be provided a suitable recess for positioning a casing C,'said casing being preferably rectangular in cross section as illustrated in Figure 2 of the drawings and comprising-the two side-walls 10, the top and bottom wall 11 and 12, respectively, and the rear wall 13. The forward end of the casing C is closed by a cover plate 14 the ends of which preferably extend beyond the top and bottom walls 11 and 12, respectively, of the casing 0. Any suitable means may be employed for securing the cover plate 14 in position, and suitable recesses may be formed in the wall in order to accommodate the extended ends of said cover plate.

To the upper or top wall 11 of the casing C there is secured a cylinder A, said cylinder having its upper end open and being formed with an annular flange 15 by which the same may be secured to the wall 11 of the casing C through the means of bolts or the like. Thelower end of the cylinder is formed with a closure 16. Within the cylinder A there is slidably positioned a piston head 17 which is secured to the one.end of a rod 18, said rod extending through the closure 16 and said closure carrying a stufi'- ing box 19 to insure against leakage of the liquid from the cylinder A. The piston head 17 is provided with a pair of vertically disposed pockets 20, each of which communicates at its lower end with an orifice 21. Within each pocket there is disposed a ball 21. Also the piston head is provided with an orifice 20. The purpose of theballs 21' and the orifice 20', will later be apparent.

Upon the lower end of the rod 18 there is secured ahead member22 which carries a clip or bridging member 23 which terminates at each end in an offset curved portion 24. Upon the one side wall 10 there is mounted a pair of insulating. members 25, each of which carries a strip of conducting material 26. The member 23 is adapted to bridge the conductor members 26 and each conductor member is connected to a wire as at 27 said wires being included in an electrical circuit for one or more lights.

Within the cylinder A there is disposed a coil spring 29 which is positioned between the bottom closure 16 of the cylinder and the piston head 17 and which is adapted to normally hold the piston 17 in such a position that the bridging member 23 is clear of the conductor members 26 and thereby normally retaining open the electrical circuit established by the wires 27.

Upon the cylinder A there is pivoted or fulcrumed as at 30 a bell crank lever 31 having its one arm 32 pivotally attached as at 33 to a lever bar 34, said lever bar 34 being fulcrumed or pivoted at a point centrally of its length as at 35, and having its other end pivotall connected as at 36 to a link 37, said link 37 eing in turn pivotally connected as at 38 to a second lever bar 39. The lever bar 39 is pivotally supported as at 40 at a point adjacent its inner end and adjacent its outer end there is provided an elongated slot 41. A pin 42 is extended through the slot 41.and secured to the clip 23 carried by the piston rod 18' thereby connecting the piston rod with the lever bar 39.

The cover plate 14 is provided with a pair of openings 43, said openings being adapted to accommodate the push buttons P and P. Each push button has its inner end formed with an extension 44 and the extension of the push button P is pivotally connected as at 45 to the remaining end of the bell crank lever 31. The free end of the extension, 44 of the plunger P is pivotally connected as at 46 to the one end of a lever bar 47, said lever bar being fulcrumed as at 48 and having its other end pivotally connected as at 49 to the one end of a link 50, said link being in turn pivotally connected as at 51 at its other end to a latch member 52. The latch member 52 may consist of a short link or bar as shown pivoted upon the bottom of the casing C and having a segmental shaped enlargement 53 formed at its other end which is adapted to "engage the associated end of the lever bar 39 when said lever bar is moved therebeneath. A coil spring 54 serves to yieldingly draw the latch 52 forwardly.

The cover plate 14 may be further supported by the means of a plate 14'. The plate 14' may be of any finish desired and has suitable openings in register with the openings 43 in the plate 14 whereby to per- Fit the operation of the push buttons P and In the operation of the present switch assuming that the circuit is connected to the wires 27 in such a manner that when such wires are connected together the circuit may be closed. As shown in Figure 1 the push button P has been depressed and the bridge member 23 is positioned between the conductor members 26 thereby connecting together the wires 27 and closing the electrical circuit referred to. Now if it is desired to open this electrical circuit the push button P is depressed and upon this occurring the lever bar 47 is actuated for swinging the latch member52 outwardly and thereby releasing the forward end of the lever bar 39 whereupon the tension of the spring 29 within thecylinder A will force the piston 17 upwardly and draw the bridging member 23 away and off from the conductor members 26 and in this way open the circuit. Now it is important to note that upon upward movement of the piston 17 the balls 21" will move over the orifice 21 and close ember the same thereby making it necessary that i the liquid must pass through the restricted orifice 20' and in this way retarding the upward movement of the plston head 17. The

diameter of the orifice 20' will, of course control the time that it would take for the bridge member 23 to disconnect the two conductors 26 and open the lighting circuit.

This delay in opening the electrical circuit after the button has been depressed for this purpose has many apparent advantages. The lights connected with a switch of this kind might be employed in a dwelling or in stores or oflices and'advantages derived therefrom. 1

In closing the electrical circuit the push button P is depressed whereupon the bell crank lever 31 will operate the lever bar 34 for lowering the forward end of the lever bar 39 until the piston 17 is drawn downit to be understood that I am aware of the fact that the construction, combination and arrangement of parts may be changed by those skilled inthe art without departing from the spirit of the invention as indicated by the appended claims.

What claim is:

1. In a device'of the character described, a pair of fulcrumed lever bars, a link connection between similar ends of the lever bars, a fulcrumed bell crank lever having one end connected to the remaining end of one of the lever bars, and a plunger connected to the other end of the bell crank lever whereby the lever bars may be rocked in llIllSOIl for the purpose described.

2. In a device of the character described, a pair of fulcrumed lever bars, alink connection between similar ends of the lever bars, a fulcrumed bell crank lever having one end connected tothe remaining end of one of the lever bars, a plunger connected to the other end of the bell crank lever whereby the lever bars may be rocked in unison, spring means to resist the movement of said lever bars in one direction, and a spring pressed latch adapted to hold the levers against movement when rocked a predetermined degree against the tension of said spring means;

I WILLIAM FARRELL FULTON. 

